Inclusion Criteria:

1. Males or females of 65 years of age or greater. Patients between the ages of 65 and
70 years of age must have 1 or more of the following comorbidities that may preclude
the use of frontline chemo-immunotherapy with fludarabine, cyclophosphamide, or
rituximab:

- creatinine clearance < 70 mL/min using the Cockcroft-Gault equation

- platelet count < 100,000/μL or hemoglobin < 10 g/dL

- clinically apparent autoimmune cytopenia (autoimmune hemolytic anemia or immune
thrombocytopenia)

- ECOG performance score = 1 or 2

2. Diagnosis of CLL/SLL that meets IWCLL diagnostic criteria (Hallek 2008)

3. Active disease meeting at least 1 of the following IWCLL criteria (Hallek 2008) for
requiring treatment:

- Evidence of progressive marrow failure as manifested by the development of, or
worsening of, anemia and/or thrombocytopenia Massive, progressive, or
symptomatic splenomegaly

- Massive nodes or progressive or symptomatic lymphadenopathy

- Progressive lymphocytosis

- Autoimmune hemolytic anemia and/or immune thrombocytopenia that is poorly
responsive to corticosteroids or standard therapy

- Constitutional symptoms

4. Measurable nodal disease by computed tomography (CT)

5. ECOG performance status of 0-2

6. Life expectancy > 4 months from randomization

7. Adequate hematologic function, defined as absolute neutrophil count (ANC) ≥ 1,000/μL
(independent of growth factor support for at least 7 days prior to screening) and
platelet count ≥ 50,000/μL (independent of transfusion and growth factor support for
at least 7 days prior to screening)

8. Adequate hepatic function, defined as serum aspartate transaminase (AST) and alanine
transaminase (ALT) < 2.5 x upper limit of normal (ULN), and total bilirubin ≤ 1.5 x
ULN

9. Adequate renal function, defined as estimated creatinine clearance ≥ 30 mL/min using
the Cockcroft-Gault equation

10. Willingness to receive all outpatient treatment, all laboratory monitoring, and all
radiological evaluations at the institution that administers study drug for the
entire study

11. Willingness of male patients, if sexually active with a female of childbearing
potential, to use an effective barrier method of contraception during the study and
for 3 months following the last dose of study drug

12. Ability to provide written informed consent and to understand and comply with the
requirements of the study

Exclusion Criteria:

1. Known involvement of the central nervous system by lymphoma or leukemia

2. History or current evidence of Richter's transformation or prolymphocytic leukemia

3. Documentation of deletion of the short arm of chromosome 17: del(17p13.1) in more
than 20% of cells examined on any pretreatment fluorescence in situ hybridization
(FISH) or cytogenetic evaluation

4. Uncontrolled autoimmune hemolytic anemia or idiopathic thrombocytopenic purpura

5. Any previous treatment (chemotherapy, radiotherapy, and/or monoclonal antibodies)
intended specifically to treat CLL/SLL

6. Received any immunotherapy, vaccine, or investigational drug within 4 weeks prior to
randomization

7. Corticosteroid use within 1 week prior to first dose of study drug, with the
exception of inhaled, topical, or other local administrations. Patients requiring
systemic steroids at daily doses > 20 mg prednisone (or corticosteroid equivalent,
see Appendix N), or those who are administered steroids for leukemia control or white
blood cell (WBC)-count-lowering are excluded.

8. Major surgery within 4 weeks prior to randomization

9. History of prior malignancy, with the exception of the following:

- malignancy treated with curative intent and with no evidence of active disease
present for more than 3 years prior to screening and felt to be at low risk for
recurrence by treating physician

- adequately treated nonmelanomatous skin cancer or lentigo maligna melanoma
without current evidence of disease

- adequately treated cervical carcinoma in situ without current evidence of
disease

10. Currently active, clinically significant cardiovascular disease or a history of
myocardial infarction within 6 months prior to randomization

11. Inability to swallow capsules or tablets, or disease significantly affecting
gastrointestinal function

12. Uncontrolled active systemic fungal, bacterial, viral, or other infection or
requirement for intravenous (IV) antibiotics

13. Known history of infection with human immunodeficiency virus (HIV)

14. Serologic status reflecting active hepatitis B or C infection

15. History of stroke or intracranial hemorrhage within 6 months prior to enrollment

16. Current life-threatening illness, medical condition, or organ-system dysfunction that
could compromise patient safety or put the study at risk

17. Requirement for anticoagulation with warfarin

18. Requirement for treatment with a strong CYP3A4/5 and/or CYP2D6 inhibitor